An-Najah Staff

Abstract Accurate positioning with pneumatic servo positioning systems is hampered by the nonlinearities occuring in the system, like nonlinear air flow-pressure relationship through the variable area orifice of the servo valve, compressibility of air, and nonlinear friction in the contacts of the piston with the cylinder walls and slide ways. To overcome the limitations of pneumatic servo positioning systems, and for the purpose of simulation and control, the nonlinearities of pneumatic servo systems must be identified and modelled. This thesis deals with experimental modelling and identification of the various components and nonlinearities of a pneumatic servo postioning system to the end of constructing a complete and effective model that can be used for simulatuion and control of pneumatic servo systems. For the purpose of solving the regulation and servo problems of pneumatic servo positioning systems, this thesis presents a new control strategy that takes into account the two basic control issues of those nonlinear systems: nonlinear flow through the orifices of the servo valve and nonlinear friction in the contacts of the piston with the cylinder walls and slide-ways.